165 research outputs found

    A guided search non-dominated sorting genetic algorithm for the multi-objective university course timetabling problem

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    Copyright @ Springer-Verlag Berlin Heidelberg 2011.The university course timetabling problem is a typical combinatorial optimization problem. This paper tackles the multi-objective university course timetabling problem (MOUCTP) and proposes a guided search non-dominated sorting genetic algorithm to solve the MOUCTP. The proposed algorithm integrates a guided search technique, which uses a memory to store useful information extracted from previous good solutions to guide the generation of new solutions, and two local search schemes to enhance its performance for the MOUCTP. The experimental results based on a set of test problems show that the proposed algorithm is efficient for solving the MOUCTP

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    Calidad de vida y función sexual en mujeres con disfunción del piso-pélvico del sur de Chile

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    Antecedentes/Objetivos: La disfunción del piso pélvico (DPP) es muy prevalente, afectando a un tercio de las mujeres adultas. Estas patologías no suponen un riesgo vital, pero sus síntomas pueden interferir con las actividades de la vida diaria incluyendo aspectos físicos, sociales y sexuales. En el sur de Chile, en el Hospital de alta complejidad (Regional-Concepción), se ha implementado la Unidad de Piso Pélvico (UPP). No hay evidencia sobre el efecto que supone en la calidad de vida y la función sexual de las mujeres que la padecen Describir la calidad de vida y función sexual de mujeres controladas en la Unidad de Piso Pélvico de un Hospital de alta complejidad en Chile. Métodos: Estudio transversal. Población: usuarias con DPP de la UPP del H. Regional-Concepción. Muestra 173. Variables: Caract. sociodemográficas, antecedentes obstétricos, tipo de DPP, Variables de Calidad de Vida (percepción del estado de salud, limitación emocional, limitación de actividades cotidianas, alteraciones de actividades sociales) (Short Form-12 Health Survey) y función sexual (PISQ-12). Análisis: medidas de dispersión, frecuencia absoluta- relativa. Resultados: Edad media 57 años, 88% con ingreso menor a 357€. 91% con IMC-sobrepeso y obesidad, 64% ≥ 3 hijos. Tipos DPP: 53% incontinencia de orina (IO), 35% prolapso vaginal (Pp), 12% IO+Pp. Calidad de vida (n = 173): Mala percepción de salud: 95%. Limitación emocional: 37%. Limitación de actividades cotidianas: 67%. Alteraciones de actividades sociales: 57% Función sexual (n = 95): Disfunción alta: 8,4%, moderada: 41,1%, baja 50,5%. El 15% nunca tuvo deseo-sexual los últimos 6 meses. El 14% admite no haber alcanzado el orgasmo en los últimos 6 meses, el mismo porcentaje admite no sentir excitación en el mismo período. El 19% admite no estar satisfechas con las actividades sexuales actuales, el 15% siente dolor durante las relaciones sexuales, el 40% admite sufrir de pérdidas de orina durante la actividad sexual, y el mismo número admite restringir su vida sexual debido al miedo de pérdida de orina durante el acto sexual. El 27% admite tener reacciones emocionales negativas durante las relaciones sexuales. El 10% y el 13% admite que sus parejas sufrían de disfunción eréctil y eyaculación, respectivamente. Por último, el 42% de las mujeres admite que sus orgasmos en los últimos 6 meses son más intensos. Conclusiones: Las mujeres con DPP presentan una alteración negativa de su calidad de vida y de su función sexual, aunque existe cierta incongruencia al valorar positivamente la calidad de los orgasmos cuando los demás aspectos de la vida sexual son negativos

    Condicionalidad reforzada a través de las cubiertas vegetales en olivar. Opinión de los agricultores

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    En el cultivo del olivar, en la última década, se ha implantado y extendido el uso de cubiertas vegetales como práctica cultural. El empleo de cubiertas vegetales en olivar se asocia a una multitud de efectos ambientales positivos y por tanto la implementación de estas en los olivares ha sido objeto de ayudas específicas en las medidas agroambientales de diferentes programas de desarrollo rural de Andalucía a partir del año 2000. Sin embargo, según los datos de la encuesta sobre Superficies y Rendimientos Cultivos del Ministerio de Agricultura, Pesca y Alimentación (Esyrce) las cubiertas vegetales en olivar sólo se emplean en alrededor de un 29% del total de la superficie del olivar andaluz. El objetivo de este trabajo es conocer la opinión de los agricultores con respecto a la puesta de cubiertas vegetales. Por ello se realizan 200 encuestas a olivareros y se determinan los factores de bloqueo y propiciadores a las mismas. Entre ellos, se analiza el impacto de una condicionalidad reforzada que obligue a los agricultores a usar cubiertas vegetales.El presente estudio ha sido financiado por el proyecto PR.AVA.AVA2019.031 cofinanciado al 80% por el Fondo Europeo de Desarrollo Regional, dentro del Programa Operativo FEDER de Andalucía 2014-2020

    Hydrogeophysical Assessment of the Critical Zone below a Golf Course Irrigated with Reclaimed Water Close to Volcanic Caldera

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    The geometry and the hydraulic properties of the unsaturated zone is often difficult to evaluate from traditional soil sampling techniques. Soil samples typically provide only data of the upper layers and boreholes are expensive and only provide spotted information. Non-destructive geophysical methods and among them, electrical resistivity tomography can be applied in complex geological environments such as volcanic areas, where lavas and unconsolidated pyroclastic deposits dominate. They have a wide variability of hydraulic properties due to textural characteristics and modification processes suh as compaction, fracturation and weathering. To characterize the subsurface geology below the golf course of Bandama (Gran Canaria) a detailed electrical resistivity tomography survey has been conducted. This technique allowed us to define the geometry of the geological formations because of their high electrical resistivity contrasts. Subsequently, undisturbed soil and pyroclastic deposits samples were taken in representative outcrops for quantifying the hydraulic conductivity in the laboratory where the parametric electrical resistivity was measured in the field. A statistical correlation between the two variables has been obtained and a 3D model transit time of water infiltration through the vadose zone has been built to assess the vulnerability of the aquifers located below the golf course irrigated with reclaimed water

    Search for Higgs bosons decaying to tautau pairs in ppbar collisions at sqrt(s) = 1.96 TeV

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    We present a search for the production of neutral Higgs bosons decaying into tautau pairs in ppbar collisions at a center-of-mass energy of 1.96 TeV. The data, corresponding to an integrated luminosity of 5.4 fb-1, were collected by the D0 experiment at the Fermilab Tevatron Collider. We set upper limits at the 95% C.L. on the product of production cross section and branching ratio for a scalar resonance decaying into tautau pairs, and we then interpret these limits as limits on the production of Higgs bosons in the minimal supersymmetric standard model (MSSM) and as constraints in the MSSM parameter space.Comment: 7 pages, 5 figures, submitted to PL

    Measurement of three-jet differential cross sections d sigma-3jet / d M-3jet in p anti-p collisions at sqrt(s)=1.96 TeV

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    We present the first measurement of the inclusive three-jet differential cross section as a function of the invariant mass of the three jets with the largest transverse momenta in an event in p anti-p collisions at sqrt(s) = 1.96 TeV. The measurement is made in different rapidity regions and for different jet transverse momentum requirements and is based on a data set corresponding to an integrated luminosity of 0.7 fb^{-1} collected with the D0 detector at the Fermilab Tevatron Collider. The results are used to test the three-jet matrix elements in perturbative QCD calculations at next-to-leading order in the strong coupling constant. The data allow discrimination between parametrizations of the parton distribution functions of the proton.Comment: 10 pages, 4 figures, 2 tables, submitted to Phys. Lett. B, corrected chi2 values for NNPD

    Search for single vector-like quarks in ppbar collisions at sqrt(s) = 1.96 TeV

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    We present a search for hypothetical vector-like quarks in ppbar collisions at sqrt(s) = 1.96 TeV. The data were collected by the D0 detector at the Fermilab Tevatron Collider and correspond to an integrated luminosity of 5.4 fb^(-1). We select events with a final state composed of a W or Z boson and a jet consistent with a heavy object decay. We observe no significant excess in comparison to the background prediction and set limits on production cross sections for vector-like quarks decaying to W+jet and Z+jet. These are the most stringent mass limits for electroweak single vector-like quark production at hadron colliders.Comment: submitted to Phys. Rev. Let

    Search for pair production of the scalar top quark in muon+tau final states

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    We present a search for the pair production of scalar top quarks (t~1\tilde{t}_{1}), the lightest supersymmetric partners of the top quarks, in ppˉp\bar{p} collisions at a center-of-mass energy of 1.96 TeV, using data corresponding to an integrated luminosity of {7.3 fb1fb^{-1}} collected with the \dzero experiment at the Fermilab Tevatron Collider. Each scalar top quark is assumed to decay into a bb quark, a charged lepton, and a scalar neutrino (ν~\tilde{\nu}). We investigate final states arising from t~1t~1ˉbbˉμτν~ν~\tilde{t}_{1} \bar{\tilde{t}_{1}} \rightarrow b\bar{b}\mu\tau \tilde{\nu} \tilde{\nu} and t~1t~1ˉbbˉττν~ν~\tilde{t}_{1} \bar{\tilde{t}_{1}} \rightarrow b\bar{b}\tau\tau \tilde{\nu} \tilde{\nu}. With no significant excess of events observed above the background expected from the standard model, we set exclusion limits on this production process in the (mt~1m_{\tilde{t}_{1}},mν~m_{\tilde{\nu}}) plane.Comment: Submitted to Phys. Lett.

    Measurements of inclusive W+jets production rates as a function of jet transverse momentum in ppbar collisions at sqrt{s}=1.96 TeV

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    This Letter describes measurements of inclusive W (--> e nu) + n jet cross sections (n = 1-4), presented as total inclusive cross sections and differentially in the nth jet transverse momentum. The measurements are made using data corresponding to an integrated luminosity of 4.2 fb-1 collected by the D0 detector at the Fermilab Tevatron Collider, and achieve considerably smaller uncertainties on W +jets production cross sections than previous measurements. The measurements are compared to next-to-leading order perturbative QCD (pQCD) calculations in the n =1-3 jet multiplicity bins and to leading order pQCD calculations in the 4-jet bin. The measurements are generally in agreement with pQCD predictions, although certain regions of phase space are identified where the calculations could be improved
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